diff options
90 files changed, 2007 insertions, 568 deletions
diff --git a/Documentation/gpu/driver-uapi.rst b/Documentation/gpu/driver-uapi.rst new file mode 100644 index 000000000000..4411e6919a3d --- /dev/null +++ b/Documentation/gpu/driver-uapi.rst @@ -0,0 +1,8 @@ +=============== +DRM Driver uAPI +=============== + +drm/i915 uAPI +============= + +.. kernel-doc:: include/uapi/drm/i915_drm.h diff --git a/Documentation/gpu/index.rst b/Documentation/gpu/index.rst index ec4bc72438e4..b9c1214d8f23 100644 --- a/Documentation/gpu/index.rst +++ b/Documentation/gpu/index.rst @@ -10,6 +10,7 @@ Linux GPU Driver Developer's Guide drm-kms drm-kms-helpers drm-uapi + driver-uapi drm-client drivers backlight diff --git a/Documentation/gpu/rfc/i915_gem_lmem.rst b/Documentation/gpu/rfc/i915_gem_lmem.rst new file mode 100644 index 000000000000..675ba8620d66 --- /dev/null +++ b/Documentation/gpu/rfc/i915_gem_lmem.rst @@ -0,0 +1,131 @@ +========================= +I915 DG1/LMEM RFC Section +========================= + +Upstream plan +============= +For upstream the overall plan for landing all the DG1 stuff and turning it for +real, with all the uAPI bits is: + +* Merge basic HW enabling of DG1(still without pciid) +* Merge the uAPI bits behind special CONFIG_BROKEN(or so) flag + * At this point we can still make changes, but importantly this lets us + start running IGTs which can utilize local-memory in CI +* Convert over to TTM, make sure it all keeps working. Some of the work items: + * TTM shrinker for discrete + * dma_resv_lockitem for full dma_resv_lock, i.e not just trylock + * Use TTM CPU pagefault handler + * Route shmem backend over to TTM SYSTEM for discrete + * TTM purgeable object support + * Move i915 buddy allocator over to TTM + * MMAP ioctl mode(see `I915 MMAP`_) + * SET/GET ioctl caching(see `I915 SET/GET CACHING`_) +* Send RFC(with mesa-dev on cc) for final sign off on the uAPI +* Add pciid for DG1 and turn on uAPI for real + +New object placement and region query uAPI +========================================== +Starting from DG1 we need to give userspace the ability to allocate buffers from +device local-memory. Currently the driver supports gem_create, which can place +buffers in system memory via shmem, and the usual assortment of other +interfaces, like dumb buffers and userptr. + +To support this new capability, while also providing a uAPI which will work +beyond just DG1, we propose to offer three new bits of uAPI: + +DRM_I915_QUERY_MEMORY_REGIONS +----------------------------- +New query ID which allows userspace to discover the list of supported memory +regions(like system-memory and local-memory) for a given device. We identify +each region with a class and instance pair, which should be unique. The class +here would be DEVICE or SYSTEM, and the instance would be zero, on platforms +like DG1. + +Side note: The class/instance design is borrowed from our existing engine uAPI, +where we describe every physical engine in terms of its class, and the +particular instance, since we can have more than one per class. + +In the future we also want to expose more information which can further +describe the capabilities of a region. + +.. kernel-doc:: include/uapi/drm/i915_drm.h + :functions: drm_i915_gem_memory_class drm_i915_gem_memory_class_instance drm_i915_memory_region_info drm_i915_query_memory_regions + +GEM_CREATE_EXT +-------------- +New ioctl which is basically just gem_create but now allows userspace to provide +a chain of possible extensions. Note that if we don't provide any extensions and +set flags=0 then we get the exact same behaviour as gem_create. + +Side note: We also need to support PXP[1] in the near future, which is also +applicable to integrated platforms, and adds its own gem_create_ext extension, +which basically lets userspace mark a buffer as "protected". + +.. kernel-doc:: include/uapi/drm/i915_drm.h + :functions: drm_i915_gem_create_ext + +I915_GEM_CREATE_EXT_MEMORY_REGIONS +---------------------------------- +Implemented as an extension for gem_create_ext, we would now allow userspace to +optionally provide an immutable list of preferred placements at creation time, +in priority order, for a given buffer object. For the placements we expect +them each to use the class/instance encoding, as per the output of the regions +query. Having the list in priority order will be useful in the future when +placing an object, say during eviction. + +.. kernel-doc:: include/uapi/drm/i915_drm.h + :functions: drm_i915_gem_create_ext_memory_regions + +One fair criticism here is that this seems a little over-engineered[2]. If we +just consider DG1 then yes, a simple gem_create.flags or something is totally +all that's needed to tell the kernel to allocate the buffer in local-memory or +whatever. However looking to the future we need uAPI which can also support +upcoming Xe HP multi-tile architecture in a sane way, where there can be +multiple local-memory instances for a given device, and so using both class and +instance in our uAPI to describe regions is desirable, although specifically +for DG1 it's uninteresting, since we only have a single local-memory instance. + +Existing uAPI issues +==================== +Some potential issues we still need to resolve. + +I915 MMAP +--------- +In i915 there are multiple ways to MMAP GEM object, including mapping the same +object using different mapping types(WC vs WB), i.e multiple active mmaps per +object. TTM expects one MMAP at most for the lifetime of the object. If it +turns out that we have to backpedal here, there might be some potential +userspace fallout. + +I915 SET/GET CACHING +-------------------- +In i915 we have set/get_caching ioctl. TTM doesn't let us to change this, but +DG1 doesn't support non-snooped pcie transactions, so we can just always +allocate as WB for smem-only buffers. If/when our hw gains support for +non-snooped pcie transactions then we must fix this mode at allocation time as +a new GEM extension. + +This is related to the mmap problem, because in general (meaning, when we're +not running on intel cpus) the cpu mmap must not, ever, be inconsistent with +allocation mode. + +Possible idea is to let the kernel picks the mmap mode for userspace from the +following table: + +smem-only: WB. Userspace does not need to call clflush. + +smem+lmem: We only ever allow a single mode, so simply allocate this as uncached +memory, and always give userspace a WC mapping. GPU still does snooped access +here(assuming we can't turn it off like on DG1), which is a bit inefficient. + +lmem only: always WC + +This means on discrete you only get a single mmap mode, all others must be +rejected. That's probably going to be a new default mode or something like +that. + +Links +===== +[1] https://patchwork.freedesktop.org/series/86798/ + +[2] https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5599#note_553791 diff --git a/Documentation/gpu/rfc/index.rst b/Documentation/gpu/rfc/index.rst index a8621f7dab8b..05670442ca1b 100644 --- a/Documentation/gpu/rfc/index.rst +++ b/Documentation/gpu/rfc/index.rst @@ -15,3 +15,7 @@ host such documentation: * Once the code has landed move all the documentation to the right places in the main core, helper or driver sections. + +.. toctree:: + + i915_gem_lmem.rst diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c index 384ff0bb6e19..422b59ebf6dc 100644 --- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -11660,11 +11660,20 @@ intel_user_framebuffer_create(struct drm_device *dev, struct drm_framebuffer *fb; struct drm_i915_gem_object *obj; struct drm_mode_fb_cmd2 mode_cmd = *user_mode_cmd; + struct drm_i915_private *i915; obj = i915_gem_object_lookup(filp, mode_cmd.handles[0]); if (!obj) return ERR_PTR(-ENOENT); + /* object is backed with LMEM for discrete */ + i915 = to_i915(obj->base.dev); + if (HAS_LMEM(i915) && !i915_gem_object_is_lmem(obj)) { + /* object is "remote", not in local memory */ + i915_gem_object_put(obj); + return ERR_PTR(-EREMOTE); + } + fb = intel_framebuffer_create(obj, &mode_cmd); i915_gem_object_put(obj); diff --git a/drivers/gpu/drm/i915/display/intel_fbdev.c b/drivers/gpu/drm/i915/display/intel_fbdev.c index ccd00e65a5fe..4af40229f5ec 100644 --- a/drivers/gpu/drm/i915/display/intel_fbdev.c +++ b/drivers/gpu/drm/i915/display/intel_fbdev.c @@ -41,6 +41,8 @@ #include <drm/drm_fb_helper.h> #include <drm/drm_fourcc.h> +#include "gem/i915_gem_lmem.h" + #include "i915_drv.h" #include "intel_display_types.h" #include "intel_fbdev.h" @@ -137,14 +139,22 @@ static int intelfb_alloc(struct drm_fb_helper *helper, size = mode_cmd.pitches[0] * mode_cmd.height; size = PAGE_ALIGN(size); - /* If the FB is too big, just don't use it since fbdev is not very - * important and we should probably use that space with FBC or other - * features. */ obj = ERR_PTR(-ENODEV); - if (size * 2 < dev_priv->stolen_usable_size) - obj = i915_gem_object_create_stolen(dev_priv, size); - if (IS_ERR(obj)) - obj = i915_gem_object_create_shmem(dev_priv, size); + if (HAS_LMEM(dev_priv)) { + obj = i915_gem_object_create_lmem(dev_priv, size, + I915_BO_ALLOC_CONTIGUOUS); + } else { + /* + * If the FB is too big, just don't use it since fbdev is not very + * important and we should probably use that space with FBC or other + * features. + */ + if (size * 2 < dev_priv->stolen_usable_size) + obj = i915_gem_object_create_stolen(dev_priv, size); + if (IS_ERR(obj)) + obj = i915_gem_object_create_shmem(dev_priv, size); + } + if (IS_ERR(obj)) { drm_err(&dev_priv->drm, "failed to allocate framebuffer\n"); return PTR_ERR(obj); @@ -178,6 +188,7 @@ static int intelfb_create(struct drm_fb_helper *helper, unsigned long flags = 0; bool prealloc = false; void __iomem *vaddr; + struct drm_i915_gem_object *obj; int ret; if (intel_fb && @@ -232,13 +243,27 @@ static int intelfb_create(struct drm_fb_helper *helper, info->fbops = &intelfb_ops; /* setup aperture base/size for vesafb takeover */ - info->apertures->ranges[0].base = ggtt->gmadr.start; - info->apertures->ranges[0].size = ggtt->mappable_end; + obj = intel_fb_obj(&intel_fb->base); + if (i915_gem_object_is_lmem(obj)) { + struct intel_memory_region *mem = obj->mm.region; + + info->apertures->ranges[0].base = mem->io_start; + info->apertures->ranges[0].size = mem->total; + + /* Use fbdev's framebuffer from lmem for discrete */ + info->fix.smem_start = + (unsigned long)(mem->io_start + + i915_gem_object_get_dma_address(obj, 0)); + info->fix.smem_len = obj->base.size; + } else { + info->apertures->ranges[0].base = ggtt->gmadr.start; + info->apertures->ranges[0].size = ggtt->mappable_end; - /* Our framebuffer is the entirety of fbdev's system memory */ - info->fix.smem_start = - (unsigned long)(ggtt->gmadr.start + vma->node.start); - info->fix.smem_len = vma->node.size; + /* Our framebuffer is the entirety of fbdev's system memory */ + info->fix.smem_start = + (unsigned long)(ggtt->gmadr.start + vma->node.start); + info->fix.smem_len = vma->node.size; + } vaddr = i915_vma_pin_iomap(vma); if (IS_ERR(vaddr)) { diff --git a/drivers/gpu/drm/i915/display/intel_frontbuffer.c b/drivers/gpu/drm/i915/display/intel_frontbuffer.c index 8161d49e78ba..8e75debcce1a 100644 --- a/drivers/gpu/drm/i915/display/intel_frontbuffer.c +++ b/drivers/gpu/drm/i915/display/intel_frontbuffer.c @@ -211,7 +211,6 @@ static int frontbuffer_active(struct i915_active *ref) return 0; } -__i915_active_call static void frontbuffer_retire(struct i915_active *ref) { struct intel_frontbuffer *front = @@ -266,7 +265,8 @@ intel_frontbuffer_get(struct drm_i915_gem_object *obj) atomic_set(&front->bits, 0); i915_active_init(&front->write, frontbuffer_active, - i915_active_may_sleep(frontbuffer_retire)); + frontbuffer_retire, + I915_ACTIVE_RETIRE_SLEEPS); spin_lock(&i915->fb_tracking.lock); if (rcu_access_pointer(obj->frontbuffer)) { diff --git a/drivers/gpu/drm/i915/display/intel_overlay.c b/drivers/gpu/drm/i915/display/intel_overlay.c index 46cba12be888..7e3f5c6ca484 100644 --- a/drivers/gpu/drm/i915/display/intel_overlay.c +++ b/drivers/gpu/drm/i915/display/intel_overlay.c @@ -384,8 +384,7 @@ static void intel_overlay_off_tail(struct intel_overlay *overlay) i830_overlay_clock_gating(dev_priv, true); } |